Many merchants provide electronic payment terminals to allow customers to purchase goods and services by means other than cash payment. The payment terminals are connected to a secure payment (acquirer) network which interfaces with the merchants' respective financial institutions. The payment terminals are deployed with proprietary software that uses the acquirer network to securely process electronic payments via payment account information received from hardware tokens (e.g. credit cards, debit cards) that may be interfaced with the payment terminals.
Merchants often locate inexpensive wares in close proximity to checkout lanes to increase the likelihood of impulse purchases. Dunstan (WO 2010/012094) expands upon this idea by using a central computer server as a trusted intermediary between the acquirer network and a second network to allow customers to use the payment terminals to access computer servers on the second network. The central server allows the computer servers of the second network to apply their security services on the acquirer network. The acquirer terminals are provided with a terminal application that supplements or replaces the existing proprietary software deployed on the acquirer terminals. The terminal applications allow the acquirer terminals to be used on the second network via the security services imposed by the central server. However, since the central server is controlled by a third party, and the terminal applications communicate with the acquirer network and the central server, the security of the acquirer network can become compromised by rogue software installed on the central server.